This invention relates primarily to the field of rotating one tubular member relative to another, about the common longitudinal axis of both such members, during the making or breaking of threaded connections between such members. The tubular members are normally pipe sections used relative to oil wells, water wells, etc., and are sometimes hereinafter called "well elements". It has been common in this field to use one tool, called a spinner, to effect relatively high-speed rotation of one pipe section relative to the other when there is but little resistance to such rotation, and then to employ another tool to tighten (torque) a joint being formed or to initially loosen (break out) a joint being disconnected. Although such two tools are sometimes on the same housing, they are conventionally separate tools and separately operated.
There is a major need in the oil well and water well industries, and others, to provide a single tool that is compact, practical, effective and economical, and that can be employed to do the spinning and torquing in one operation--without changing tools or changing from one part of a tool to another part thereof. It is, however, not meant to be implied that any such combination tool can achieve the very high torques required in some types of joints. Instead, it is the purpose to indicate that there are many types of joints, for example in pump service, water drilling, core drilling and exploration drilling, where a single tool incorporating the present invention can perform both spinning and torquing in one operation. Such spinning and torquing in one operation increases productivity, lowers operational costs, and is relatively safe and fast.
It is highly important that such a tool be relatively small and compact, as well as being much lighter than many spinning and torquing tools in the prior art. The tool must be adapted to effect the spinning and torquing functions when the pipe sections are either vertical or horizontal, and must have the ability to control torque in order to reduce the risk of damage to threaded connections.
It is of distinct importance that the tool be adapted to spin and torque pipes having substantially different outer diameters. For example, one embodiment of the present tool is adapted to be employed relative to pipe sections ranging from 23/8 inches in diameter to 51/2 inches in diameter. The changing from operation on a pipe of one diameter, to operation on a pipe of another diameter, must be effected relatively rapidly and easily and in a substantially foolproof manner.
The tool should be such that it will open wide so as to be able to swing easily on or off the threaded connection. It should also be such that there is no need to make any part excessively massive and heavy for the function that it performs. The tool must be such that the pipe sections are very firmly gripped without, however, causing the pipe sections to be cut, crushed or excessively marred.